While the federal government recommends that Florida schools test for radon every five years, we uncovered that it's not happening.

Lee Grooms' daughter Jada goes to Bayshore Elementary School.

"She likes to read," dad said. He's never been worried about her health at school until we showed him the testing results.

Radon is colorless, odorless, and tasteless.

"If there's something that could be seeping through the floors, they should at least check for it once a year," Grooms said. Bayshore Elementary hasn't been tested since 1997.

Out of 83 public and private schools that have previously been tested for radon, 77 percent of them has not been tested since 1996.

The schools aren't doing anything wrong because mandatory radon testing is not required in Lee or Collier counties.

Dr. Matthew Schabath, an epidemiologist at Moffitt Cancer Center and Research Institute in Tampa, says just because a classroom tested low for radon 20 years ago doesn't mean it will test low now.

"It's like a flowing river," said Schabath. "It can ebb and flow. It's something that requires constant measurement over time.

Radon testing is required in Charlotte County because of where it’s located on this Florida Radon Protection Map, but it's only required in brand-new schools.

And, if elevated radon levels are found, mitigation is recommended, but it's not required.

The last testing we've done are the two newest schools that we built," said Mike Riley, spokesperson for Charlotte County Public Schools. "I want to emphasize that we follow the law and whatever comes down from the state."

The NBC2 Investigators reached out to every school that had classrooms with radon levels over four picocuries, dating back to 1994.

A spokesperson for the School District of Lee County said, "I spoke with our Maintenance Department Supervisor, and they respectfully decline to participate in your story."

A spokesperson for Collier County Public Schools said, "We do not test for radon."

A spokesperson for the Diocese of Venice in Florida that covers Bishop Verot High, St. Andrew Catholic School, St. Francis Xavier, and St. John Neumann High said, "Thank you again, but these are not public schools and are not subject to the aforementioned public records request."